As the use of computers and computer networks has increased dramatically in recent years, so too have concerns regarding the security of information stored on and transmitted between computer devices.
One problem commonly encountered is the problem of providing network security for networks that contain sensitive or otherwise confidential data. A challenge occurs, for example, when multiple networks or sub-networks having different levels of security are interconnected. In the case of private entities that interact with government agencies, for example, government agencies may wish to only transmit or receive information to or from the private entities without allowing these entities direct, two-way access to sensitive networks or network devices. Safeguards placed within sensitive networks (e.g., government networks, corporate networks, etc.), can be used to provide a security boundary that prevents outside access to internal networks, and maintains a zone of integrity, where all information is known to be secret, sanitized, and authentic. Such zones of integrity are sometimes referred to, for example, as demilitarized zones (DMZs). Transmitting data across network boundaries (e.g., between networks having different levels of security) is a sensitive task for which appropriately secure mechanisms must be employed.
In the past, systems have generally focused on two-way data transfers, and maintaining the integrity of two-way data communications channels, such as in commercial applications on the Internet, including secure socket layer (SSL) communications, and other techniques, for example. Because of the security requirements for some network security boundaries, however, a mechanism that can ensure a one-way transfer of data across such boundaries is often desirable.
Some prior systems that intend to maintain the integrity of a network use software applications to control devices that are capable of bidirectional communications for providing only a one-way data channel between networks. Such systems can, for example, use devices with both transmit and receive capabilities, but only process data either for a transmitter or from a receiver. Other such systems may, for example, allow two one-way communications channels to be established by a bidirectional capable device: one for transmitting data and one for receiving data. Still other approaches attempt to fool or “spoof” devices into believing they are engaged in two-way communications with another device across a security boundary, when they are actually only transmitting data to or receiving data from that device.
In the context of wireless communications and wireless data transfer, security over one-way data paths has been addressed in a limited context. For example, U.S. Pat. No. 6,317,831 to King entitled, “Method and Apparatus for Establishing a Secure Connection over a One-Way Data Path,” discloses performing cryptographic handshake operations for a one-way data channel over a companion two-way data channel to satisfy security protocols that require two-way communications for such operations.
Each of the prior approaches has the inherent security risks of the possible flow of data in an undesired direction. In some applications, such as communications across government network security boundaries, communications across sensitive corporate network security boundaries, or other communications across similarly sensitive network security boundaries, using a two-way data channel of any type, or any devices capable of two-way communication is undesirable and/or unacceptable. In such sensitive contexts, a two-way channel, or even the ability to establish such a two-way channel, can pose an unacceptable security risk or data integrity risk.
Accordingly, it would be desirable to develop a mechanism for one-way transfer of data that does not pose the security and data integrity risks associated with prior approaches. Such a method and system should be simple to employ within existing network architectures and protocols, and should provide a high-speed, guaranteed one-way transfer mechanism that permits one-way streaming of high-bandwidth data.